As is known golf course sand traps or bunkers are pits filled with sand and surrounded by turf. Such bunkers typically contain approximately 4-6 inches of sand on the bottom of the pit, tapering to a thickness of 2 inches on the sides. Normal usage and the weather tend to cause the sand to slide down of the bunker, particularly if the sidewalls are relatively steep. This action may result in mixing of the sand with subsurface materials. One technique frequently used to prevent the mixing of the sand with substrate materials is to use a geotextile fabric blanket or mat as a bunker liner. In particular, a geotextile blanket or mat is laid in the pit forming the bunker and is stapled to the sidewalls about the perimeter of the pit. The edges of the blanket typically extend under the turf at the perimeter of the bunker.
While the use of such fabrics may impede mixing of the bunker sand with the substrate material and may facilitate drainage, the use of such geotextile blankets is not without its own problems. For example, the installation of such blankets or mats is somewhat expensive and requires a great deal of hand labor to install since they are typically laid in sections and anchored in place with numerous staples. Moreover, the fabric making up such blankets or mats is relatively smooth and when in place does not deter sand from sliding down the bunker's sidewall, particularly when subjected to heavy traffic and/or rainfall. That action may expose the blanket or mat, rendering the bunker unsightly. Even if not exposed, the portions of the blanket or mat located close to where the turf grass meets the edge of the bunker and where the layer of bunker sand is the thinnest, are susceptible to being pulled up and damaged during routine maintenance of the bunker. For example, the exposed portions of the blanket or mat may be snagged during manual or power raking of the bunker sand or on edging of the surrounding turf grass.
Other techniques have been used in the prior art to stabilize the sand within a bunker, such as the use of a layer of gravel or some other particulate material to line the pit forming the bunker, and with an adhesive or some other material sprayed onto the particulate material. See for example, U.S. Pat. No. 8,529,159 (Lemons).
Other prior art systems for lining a golf bunker are found in U.S. Pat. No. 4,960,345 (Hurley et al.); U.S. Pat. No. 5,746,546 (Hubbs et al.): U.S. Pat. No. 5,848,856 (Bohnhoff); U.S. Pat. No. 6,467,991 (Joyce et al.); U.S. Pat. No. 6,863,477 (Jenkins et al.); U.S. Pat. No. 7,207,747 (England); U.S. Pat. No. 7,344,340 (Carlson et al.); U.S. Pat. No. 7,699,562 (Clark); and U.S. 2004/0156679 (Jenkins).
As of the present time no prior art system exists for low cost installation and long term usage in a bunker to maintain the stability of the sand in the bunker, while enabling the safe and easy edging of the turf grass at the border of the bunker, yet which enables water to effectively drain from the bunker, and which is sufficiently flexible to readily absorb impact without damage. The subject invention addresses that need.